1. Field of the Invention
The present invention relates generally to a waste toner cartridge, and more specifically to a waste toner cartridge that can firmly hold thereon a plug, which is to be used to seal an entrance of the cartridge, thereby preventing an accident separation of the plug from the cartridge when the plug is not in use and stowed on the cartridge.
2. Description of the Related Art
FIG. 1 shows a conventional waste toner cartridge 10 for use in an image forming apparatus, comprising a housing 12 and a plurality of plugs 14. The housing 12 includes a plurality of U-shaped recesses 124 each defined by a bottom wall 16 and a U-shaped periphery wall 18 having a flange 182 with an arc section 184 and two straight sections 186 respectively extending from two ends of the arc section 184. Each of the plugs 14 has a head portion 142 and a body portion 144 axially extending from the head portion 142 and received in one of the U-shaped recesses 124 and abutted against the flange 182, as shown in FIG. 2. When waste toner is collected in the waste toner cartridge 10, the plugs 14 can be removed from the U-shaped recesses 124 and then respectively plugged into entrances 126 of the waste toner cartridge 10 to close the waste toner cartridge 10.
As shown in FIG. 2, because the body portion 144 of the plug 14 has an outer diameter smaller than a distance defined by the straight sections 186 of the flange 182, the plug 14 may come off through an open end of the U-shaped recess 124; and further, because the body portion 144 of the plug 14 has a radius approximately equal to a radius of curvature of the arc section 184 of the flange 182, the plug 14 may easily drop out of the U-shaped recess 124 along a direction perpendicular to the bottom wall 16. Under this circumstance, a user usually uses a tape to retain the plugs 14 in the U-shaped recesses 124. As a result, the user has to peel off the tape before taking the plugs 14 out of the U-shaped recesses 124, causing inconvenience to the user when using the waste toner cartridge 10.